Perpetual calendar



' Feb. 15, 1944. Y. T. DANG I PERPETUAL CALENDAR 2 Sheets-Shet 1 Filed Dec. 28, 1940 R Y me E N N R W m m D Q/T T. A G N W M Patented Feb. 15, 1944 UNITED STATES PATENT OFFICE.

PERPETUAL CALENDAR Young T. Dang, Oakland, Calif.

Application December 28, 1940, Serial N 0. 372,107

4 Claims.

The invention relates to a perpetual calendar which is arranged for the presentation of calendar data for one month at a time.

An object of the invention is to provide a simplified perpetual calendar which comprises a minimum number of elements and requires a minimum amount of printing thereon to provide the necessary data.

Another object is to provide a unitary assembly of elements which is readily and simply changeable to display appropriate day and date tabulations for successive calendar months.

A further object is to provide a structure which is equally adapted for its hanging or stand-up support in position for reference.

The invention possesses other objects and features of advantage, some of which, with the'foregoing, will be set forth in the following description of a typical embodiment thereof, and in the accompanying drawings, in which,

Figures 1 and 2 are opposite face views of a printed month-designating element of a typical embodiment of the calendar.

Figure 3 is a perspective view indicating the manner of assembling the element of Figure 1 with day-and-date leaf elements to provide a unitary calendar structure.

Figure 4 is a perspective view showing the assembled calendar unit as arranged for its hanging support on a wall.

Figures 5 and 6 are transverse sections of the calendar assembly taken respectively in planes including the lines 5-5 and 6-6 in Figure 4, an operatively installed fastening element of Figure 4 being shown in Figure 6 as longitudinally removed from its operative position.

Figures 7 and 8 are opposite face views of a printed sheet providing a pair of the calendar leaves.

Figures 9 and 10 are opposite face views of a printed sheet providing a second pair of the calendar leaves.

Figures 11 and 12 are transverse sections taken generally at the line H-l I in Figure 4 and having the elements releasably fixed together, with the calendar respectively shown as hung up on a wall and standing up on a support surface.

' As particularly illustrated, the calendar M of my invention essentially comprises a flat element [5 and four calendar leaves is and I1 and i8 and I9 arranged to be variably and collectively associated to display the appropriate data for any desired calendar month. The element l4 and the calendar leaves are of appropriately stiff and durable sheet material such as cardboard and/or Celluloid, have suitable indicia provided on their faces as by printing, and may have their faces protected as by transparent coatings over the indicia.

The element I5 is preferably shaped as a regular six-pointed star having the side edges 2| of 'its points 22 forming sixty degree angles with each other, whereby the side edges 2i of points 22 at opposite sides of a given point and extending from the base of the latter are mutually aligned. The six different points 22 of the element [5 have individual indicia 23 designating the different calendar months provided on both faces thereof whereby to jointly provide for the twelve months of the Gregorian calendar. In association with each month indicia 23, the number of calendar days in that month is also stated by indicia 24, the indicia for February also indicating either twenty-eight or twenty-nine days because of leap years. Preferably, and as shown, the sets of indicia 22 and 23 are each arranged symmetrically about the geometric center of the element l5, with at least the month indicia 22 provided beyond the line of mutually aligned edges 2!. I Q

In the present structure, the calendar leaves It and I! are provided as integral parts of a sheet 25, and the leaves 18 and I9 comprise integral parts of a' sheet 26. The sheets 25 and 26 are of like size and shape and are intermediately bendable at fold lines 21 to define the leaves thereof, the four leaves thus defined being of like size and jointly providing eight faces or pages for receiving calendar tabulations and/or other printing. Since a given day of a month may occur on any one of the seven week days, and some months have thirty-one days, seven of the leaf faces are utilized to present different day-and-date tabulations, said tabulations being differentiated by having the first day of the month on a different day of the week and all carrying through as for a thirty-one day month.

As particularly shown, the leaf i6 is provided with datetabulations 3| and 32 on the opposite faces thereof and respectively beginning on Sunday and Tuesday, the leaf I1 is similarly provided with tabulations 33 and 34 respectively beginning on Monday and Wednesday, the leaf I8 is similarly provided with tabulations 35 and 36 respectively beginning with Thursday and Saturday,

and one face of the leaf I9 is provided with a tabulation 31 beginning on Friday; it will be noted the date numbers occur on different days for the different tabulations. For presenting the various tabulations to occupy like areas on the leaves, the day numbers which occur on and after the fifth Saturday in the tabulations 36 and 31 of the sheet 23 may be placed in the top row with the first day of the month, as is shown. The face of the leaf l9 lacking a day-and-date tabulation may contain directions and/or other information as desired, and the precise order of arrangement of the seven day-and-date tabulations 3| to 3! on the different faces of the leaves IE to I9 is understood to be immaterial.

It will now be noted that each of the sheets 25 and 26 is provided with a slot 28 intermediately in its fold line 21 for receiving a point 22 of the month-designating element l5 therethrough while the sheet is folded to bring its leaves opposite each other as in Figures 3 to 6 and 8 and 10. The likeness of the sheet forms permits a nesting of either folded sheet within the other to align the slots 28 and provide for the protrusion of a point 22 of the element i5 beyond the fold line while the rest of the element is concealed within the fold of the sheets. The degree of extension of the exposed point 22 is limited by the engagement of the aligned element edges 2| at the base of the point with the bend of the inner sheet, and the slots 28 are preferably no longer than necessary to receive the point and thereby center the point and element with respect to the four leaves IE to l9 provided by the sheet assembly.

Inthe present instance, the days-per-month indicia 24 on the points 22 are provided at points ofithe element l5 inwardly of the lines of the aligned pairs of edges 2|, and the slots 28 are appropriately widened to permit the viewing of the indicia 24 simultaneously with a viewing of the corresponding month indicia 23; this feature is brought out in Figure 4.

' Having the described elements, a calendar for a particular month of any year may readily be provided by an appropriate assembly thereof. Assuming, for instance, that a calendar is to be provided for the month of December of the year 1940, and knowing that the first day of this particular month occurs on Sunday, the folded sheets 25 and 26 are nested together with the sheet 25 to expose the tabulation 3| of the leaf H5 at an outer face of the resulting stack-like assembly of the four leaves. The element I5 is then inserted within the fold of the sheets to extend the point 22 thereof bearing the indicia 23 and 24 for December beyond the leaf stack for its viewing from the same side thereof as the tabulation 3| of the leaf I6: the final result of this particular association of elements is shown in Figure 4. When the present elements are to be used to provide a calendar for a different month, it is merely necessary to rearrange and reassemble the elements in accordance with the requirements for the different month.

The star points 22 of the element l5 are provided with perforations 3B in a symmetric arrangement with respect to the element, and the perforations of the extending point of the assembled calendar may removably receive a supporting nail 39 or the like for a hanging support of the calendar in the manner indicated in Figures 4 and 11. When the calendar I4 is hung up in this manner, it will be understood that the leaves may be supported on and from the element perforations 38 are provided in the radial center lines of the points 22.

Means are preferably provided for securing the assembled calendar elements in unitary association, said means also providing for a stand-up disposal of the calendar. As particularly shown, perforations or holes 4| are provided through the various sheets IE to I9 for alignment with perforations 38 of the element I5 when the latter is fully engaged in the folds of ,the sheets 25 and 26 to expose only the point 22 which extends through the slots 28. Paper fasteners 42 having split shanks of bendable material may be applied at the holes 38 and 4| which register in the assembly for a transverse bending of the outer shank portions in a well-known manner to temporarily rivet the engaged elements together.

In the present, instance, the holes 4| are provided at upper points of the leaves for registration with holes 38 of the points of the element l5 which lie adjacent the point which extends to display the desired month designation23, -It will be understood, however, that the holes. 4| might be located elsewhere in the leaves, and might register with holes other than the holes 38 to provide for the operative installation of fasteners 42 or the like, Also, the holes 39 are arranged to loosely receive the fastener shanks to permit their alignment independently of which of the sheets 25 or 26 is inside of the other, it being noted that the leaves of the inside sheet extend slightly below those of the outside sheet; in the present instance, the holes 4| are elliptical.

When the assembled calendar is to be hung up, one or more fasteners 40 may be applied through all four leaves IE to l9 andthe-element I5, as is illustrated in Figure 11; this tends to hold the elements flat together and permits a handling of the assembly without relative dislocations of its elements. The nail 39 may extend from an upright wall or other supporting structure.-

By securing only the two frontleaves of the leaf assembly to the member I5, as is shown in Figure 12, th present calendar may be arranged to stand up in the manner of an easel upon a supporting surface. This arrangement for the standing up of the calendar provides the frontface of the extending point 22 substantially in the oblique plane of the front calendar leaf for viewing the tabulation of the latter. It will be understood that the lower edges of the inner calendar leaves jointly provide the base for the standing calendar. The calendar may also be hung up as before when the fasteners are applied as described.

From the foregoing description, taken in connection with the accompanying drawings, the advantages of the invention will be readily under stood by those skilled in the art to which the invention appertains. While I have described the features of assemblies which I now consider to comprise a preferred embodiment of the invention, I desire to have it understood that the showing is primarily illustrative, and that such changes may be made, when desired, as fall within the scope of the following claims.

I claim: r

1. In a perpetual calendar, a flat element having a regular star-shaped outline in which the side edges of alternate points which arecoterminous with the different side edges of the point between them are mutually aligned, at least four leaf elements of like size and outline having day-anddate tabulations provided on seven different faces thereof, the like numbers of the different said tabulations occurring on different week days, and means for supporting said leaf elements in a stack thereof and from a pair of aligned said edges of the first element and in variable order to present a selected tabulation thereof at the front of r the stack while presenting the star point between the said edges beyond the stack and concealing the balance of the element providing the point, said means comprising the connection of the leaf elements in pairs at opposite end portions of their top lines to receive the extending point of the first element between their connected portions while the latter rest on the said aligned edgesof the first element as the support means for the leaf elements. I

2. In a perpetual calendar, a fiat element of symmetrical outline providing a plurality of points having mutually aligned edge portions extending oppositely from th bases of the points, said element bearing indicia designating different calendar months on the'faces of its different said points, like leaves integrally connected solely at end portions of a common fold line at their tops and having all different day-and-date tabulations provided on the different faces thereof and receiving said first element between them with a point of the element extending between and beyond the connected portions of the fold line' to engage said edge portion at the base of the extending point with the fold.

3. A structure in accordance with claim 2 whereof the first element is six-pointed and bears indicia for each of the twelve calendar months on its different point faces, and there are solely two pairs of connected leaves for mutually nested mounting upon the first element.

4. A- calendar structure in accordance with claim 2 having the points of the first element provided with perforations in a symmetrical arrangement with respect to the element, and having the leaf elements provided with perforations for registration with a said perforation of the portion of the first element between them when a point of the first element extends from between the leaf elements to expose a month index thereon, and a fastener member for releasable and operative disposal through said aligned perforations for securing the elements in unitary association.

YOUNG T. DANG. 

